Fetal Fibronectin


To assist in assessing for premature labor.

Patient Preparation
There are no food, fluid, activity, or medication restrictions unless by medical direction.

Normal Findings
(Method: Immunoassay) Negative (Less than 0.05 mcg/mL).

Critical Findings and Potential Interventions


(Study type: Body fluid, swab of vaginal secretions; related body system: Reproductive system. The specimen should be promptly delivered to the laboratory.) Fibronectin is a protein found in fetal connective tissue, amniotic fluid, and the placenta of pregnant women. Placental fetal fibronectin (fFN) is concentrated in the area where the placenta and its membranes are in contact with the uterine wall. It is first secreted early in pregnancy and is believed to help implantation of the fertilized egg to the uterus. Fibronectin is not detectable again until just before delivery, at approximately 37 wk. If it is detected in vaginal secretions at 22 to 34 wk of gestation, delivery may happen prematurely. The test is a useful marker for impending membrane rupture within 7 to 14 days if the level rises to greater than 0.05 mcg/mL.


Investigate signs of premature labor.

Interfering Factors

Other Considerations:

If signs and symptoms persist in light of negative test results, repeat testing may be necessary.

Potential Medical Diagnosis: Clinical Significance of Results

Positive Findings In:

  • Premature labor (possibly initiated by mechanical or infectious processes, the membranes pull away from the uterine wall and amniotic fluid containing fFN leaks into endocervical fluid)

Nursing Implications

Before the Study: Planning and Implementation

Teaching the Patient What to Expect

  • Inform the patient this test can assess for risk of preterm delivery.
  • Explain that a vaginal swab sample is needed for the test.
  • Review the procedure with the patient. Address concerns about pain and explain that there should be no discomfort during the procedure.
  • Positioning for this study is on the gynecological examination table with the feet up in stirrups. The patient's legs are draped to provide privacy and to reduce chilling. A small amount of vaginal secretion is collected using a special swab from an fFN kit.

Potential Nursing Actions

  • Ensure that the patient knows the symptoms of premature labor, which include uterine contractions (with or without pain) lasting 20 sec or longer or increasing in frequency, menstrual-like cramping (intermittent or continuous), pelvic pressure, lower back pain that does not dissipate with a change in position, persistent diarrhea, intestinal cramps, changes in vaginal discharge, or a feeling that something is wrong.
  • Emphasize the importance of notifying the health-care provider (HCP) if contractions occur more frequently than four times per hour.

After the Study: Potential Nursing Actions

Treatment Considerations

  • Discuss the implications of abnormal test results on the patient's lifestyle. Provide teaching and information regarding the clinical implications of the test results, as appropriate. Educate the patient regarding access to counseling services.
  • Reinforce education on signs and symptoms of labor, as appropriate. Inform the patient that hospitalization or more frequent prenatal checks may be ordered.
  • Explain that other therapies may also be administered, such as antibiotics, corticosteroids, and IV tocolytics. Advise on the importance of completing the entire course of antibiotic therapy, if ordered, even if no symptoms are present.

Followup Evaluation and Desired Outcomes

  • Acknowledges information given by the HCP regarding further testing, treatment, or referral to another HCP, including the possible causes and increased risks associated with premature labor and delivery.

Fetal Fibronectinis the Nursing Central Word of the day!